Re: [PATCH v7 33/41] x86/shstk: Introduce map_shadow_stack syscall

From: Borislav Petkov
Date: Fri Mar 10 2023 - 15:05:31 EST


On Fri, Mar 10, 2023 at 05:12:40PM +0000, Edgecombe, Rick P wrote:
> > Can we use distinct negative retvals in each case so that it is clear
> > to
> > userspace where it fails, *if* it fails?
>
> Good idea, I think maybe ERANGE.

For those two, right?

/* If there isn't space for a token */
if (set_tok && size < 8)
return -EINVAL;

if (addr && addr <= 0xFFFFFFFF)
return -EINVAL;

They are kinda range-checking of sorts. A wider range but still
similar...

--
Regards/Gruss,
Boris.

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